104 CHAPTER 11: S OFTWARE UPGRADE AND INSTALLATIONsystem configuration file includes a record of the Webcache softwareversion that was running when the configuration was saved.The Restore Configuration operation restores the system configurationfrom the file to the Webcache. It checks that the system configurationbeing restored was created on the same Webcache software version asthe one that the Webcache is running.ExampleYou perform a software upgrade and experience problems with theWebcache. You now want to return the Webcache to a previous workingsoftware version. You need to install the previous software version andthen restore the configuration that you saved prior to commencing theupgrade.To do this, you need to install the software image of the previoussoftware version. This is available either on the CD supplied with theWebcache or on the 3Com FTP site. The same software image is used forinstallation and for upgrades.You need to perform a software installation to return the Webcache to aprevious working software version. All of the Webcache’s configurationsettings are lost after a software installation has been completed, exceptthe IP and DNS configuration. You should now browse to the Webcache’sWeb interface and restore the system configuration file that you savedthe last time the Webcache was running this older software version. Youwould perform the Restore Configuration command to go back to a fullyconfigured Webcache running the previous software version.If you had not previously saved a system configuration file for the oldersoftware version, you would still be able to install a previous softwareimage, but you would have to re-enter all of the configuration settings.CAUTION: You cannot restore a system configuration which was createdon a different software version to the version that the Webcache iscurrently running.Example: You save a configuration when the Webcache is runningsoftware version 1.00. You later perform a software upgrade to version1.01 and attempt to restore the 1.00 system configuration to theWebcache. The Web interface will not allow you to restore theconfiguration.Therefore you should save a configuration file for each different softwareversion that you run on the Webcache. If you need to go back to an
